NAME
Catmandu::Store::MongoDB - A searchable store backed by MongoDB
SYNOPSIS
# On the command line
$ catmandu import -v JSON --multiline 1 to MongoDB --database_name bibliography --bag books < books.json
$ catmandu export MongoDB --database_name bibliography --bag books to YAML
$ catmandu count MongoDB --database_name bibliography --bag books --query '{"PublicationYear": "1937"}'
# In perl
use Catmandu::Store::MongoDB;
my $store = Catmandu::Store::MongoDB->new(database_name => 'test');
my $obj1 = $store->bag->add({ name => 'Patrick' });
printf "obj1 stored as %s\n" , $obj1->{_id};
# Force an id in the store
my $obj2 = $store->bag->add({ _id => 'test123' , name => 'Nicolas' });
my $obj3 = $store->bag->get('test123');
$store->bag->delete('test123');
$store->bag->delete_all;
# All bags are iterators
$store->bag->each(sub { ... });
$store->bag->take(10)->each(sub { ... });
# Search
my $hits = $store->bag->search(query => '{"name":"Patrick"}');
my $hits = $store->bag->search(query => '{"name":"Patrick"}' , sort => { age => -1} );
my $hits = $store->bag->search(query => {name => "Patrick"} , start => 0 , limit => 100);
my $hits = $store->bag->search(query => {name => "Patrick"} , fields => {_id => 0, name => 1});
my $next_page = $hits->next_page;
my $hits = $store->bag->search(query => '{"name":"Patrick"}' , page => $next_page);
my $iterator = $store->bag->searcher(query => {name => "Patrick"});
my $iterator = $store->bag->searcher(query => {name => "Patrick"}, fields => {_id => 0, name => 1});
# Catmandu::Store::MongoDB supports CQL...
my $hits = $store->bag->search(cql_query => 'name any "Patrick"');
DESCRIPTION
A Catmandu::Store::MongoDB is a Perl package that can store data into
MongoDB databases. The database as a whole is called a 'store'.
Databases also have compartments (e.g. tables) called Catmandu::Bag-s.
METHODS
new(database_name => $name, %connectio_opts)
new(database_name => $name , bags => { data => { cql_mapping =>
$cql_mapping } })
Create a new Catmandu::Store::MongoDB store with name $name. Optionally
provide connection parameters (see MongoDB::MongoClient for possible
options).
The store supports CQL searches when a cql_mapping is provided. This
hash contains a translation of CQL fields into MongoDB searchable
fields.
# Example mapping
$cql_mapping = {
indexes => {
title => {
op => {
'any' => 1 ,
'all' => 1 ,
'=' => 1 ,
'<>' => 1 ,
'exact' => {field => [qw(mytitle.exact myalttitle.exact)]}
} ,
sort => 1,
field => 'mytitle',
cb => ['Biblio::Search', 'normalize_title']
}
}
}
The CQL mapping above will support for the 'title' field the CQL
operators: any, all, =, <> and exact.
The 'title' field will be mapped into the MongoDB field 'mytitle',
except for the 'exact' operator. In case of 'exact' both the
'mytitle.exact' and 'myalttitle.exact' fields will be searched.
The CQL mapping allows for sorting on the 'title' field. If, for
instance, we would like to use a special MongoDB field for sorting we
could have written "sort => { field => 'mytitle.sort' }".
The CQL has an optional callback field 'cb' which contains a reference
to subroutines to rewrite or augment the search query. In this case, in
the Biblio::Search package contains a normalize_title subroutine which
returns a string or an ARRAY of string with augmented title(s). E.g.
package Biblio::Search;
sub normalize_title {
my ($self,$title) = @_;
# delete all bad characters
my $new_title =~ s{[^A-Z0-9]+}{}g;
$new_title;
}
1;
bag($name)
Create or retieve a bag with name $name. Returns a Catmandu::Bag.
client
Return the MongoDB::MongoClient instance.
database
Return a MongoDB::Database instance.
drop
Delete the store and all it's bags.
Search
Search the database: see Catmandu::Searchable. This module supports an
additional search parameter:
- fields => { <field> => <0|1> } : limit fields to return from a query (see L<MongoDB Tutorial|
https://docs.mongodb.org/manual/tutorial/project-fields-from-query-results/>)
SEE ALSO
Catmandu::Bag, Catmandu::Searchable , MongoDB::MongoClient
AUTHOR
Nicolas Steenlant, <nicolas.steenlant at ugent.be>
CONTRIBUTORS
Johann Rolschewski, <jorol at cpan.org>
LICENSE AND COPYRIGHT
This program is free software; you can redistribute it and/or modify it
under the terms of either: the GNU General Public License as published
by the Free Software Foundation; or the Artistic License.
See
http://dev.perl.org/licenses/ for more information.
